Curved file holder



y 6, 1958 H. c. CRAWFORD- 2,833,025

' CURVED FILE HOLDER Filed April 20. 1953 /A/ 1/ EN 7 0g. A e/7nd 6: Crave/"J United States Patent CURVED FILE HDLDER Herman C. Crawford, El Segundo, Calif, assignor to Northrop Aircraft, Inc., Hawthorne, Calif, a corporation of California Application April 20, 1953, Serial No. 349,825

1 Claim. (Cl. 29-80) My invention relates to the field of hand tools and more particularly that type used in filing operations.

The art of filing has long needed an inexpensive file having a longitudinally curved contact surface. Where parts to be filed are adjacent another metal surface, filing with a straight file results in digging therein or nicking the surface even when considerable care is exercised. Therefore, an arcuated file is generally desirable. At present files having such configurations are rather expensive, and should different degrees of coarseness be required, a set of such files would have to be retained, thus adding to the expense. The aforementioned need may be satisfied by utilizing straight files, which are rather inexpensive by comparison, in conjunction with a frame slightly curved longitudinally on which the file may be mounted and held in a slight longitudinal curve by a retaining member and parts of said frame.

It is, therefore, a general object of my invention to provide an inexpensive longitudinally curved filing tool.

Another object of my invention is the utilization of a straight file in conjunction with a slightly curved file holder to obtain a longitudinally curved filing surface.

For a complete disclosure of my invention, a detailed description of a preferred embodiment will now be given in connection with the accompanying drawings forming a part of the specification, wherein:

Figure 1 is a perspective view of a file to be used in conjunction with a retaining frame and holding member similarly shown in perspective.

Figure 2 is a perspective view of the assembled invention with the frame and the retaining member turned over and end for end. I

Figure 3 is a fragmentary perspective view of the slightly curved retaining holder at the tang holding end.

Figure 4 is a section on the line 4-4 in Figure 2.

Referring to the figures, the invention comprises a fiat file member 1, a retaining member 2, a frame 3 preferably of channel construction having a slightly curved face and a handle 4. The upper surface 7 of the frame 3 is curved to allow the file 3 to be bent around it with the stress therein evenly distributed.

The frame 3 is formed at one end with a clip 5 for retaining the forward end 6 of the file 1. At the opposite end of the back of the frame 3 is an upstruck lug 9 having a hole 10 therethrough. A holding knob 11 is provided at the front end of the back of frame 3 to aid in holding the inventive device during the filing operation. Placed over the tang of the file 1, which may be any conventional type straight file, is a retaining member 2 which is channeled to reduce the weight factor, having a hole 12 through an end wall 12a adapted to allow the tang 13 of the file 1 to pass through, and an extension or tongue 14. Welded or brazed to the frame 3 between the side members thereof at the remote end from the clip 5 is a plate 18 which encloses that portion of the frame 3, thus forming an open socket 19 into which the extension 14 may be seated. A second upstruck lug 15 having a hole 16 therethrough is provided on the retaining member 2 which may be secured to the frame 3 by any convenient bolt and nut arrangement or its equivalent. In the particular. embodiment shown, the hole 16 is tapped and a thumb screw 17 is extended through the hole 10 and the tapped hole 16, thus enabling the frame 3 and the retaining member to be secured. The handle 4 is placed on the tang 13 of the file 1 after the retaining member 2 is disposed thereon.

The curved section 7 must be designed so that the bending moment placed on the file 1 will not be sufiicient to cause the usually brittle member to break.

The operation and assembly of the invention is rather simple. The forward end 6 of the file 1 is inserted in the clip portion 5 of the frame 3. The retaining member 2 is slipped over the tang 8 of the file 1 and the latter is then bent over the curved surface 7 of the frame 3 until the extension 14 of the member 2 is able to be seated within the open socket 19. The handle 4 is then placed on the tang 13 of the file 1 and the thumb screw 17 is extended through the tapped hole 16 and tightened, thus precluding loosening of the component elements through inadvertent contacts of the retainer with the work during the filing operation. Under normal conditions of use, the friction of the extension 14 in the slotor socket 19 is sufiicient' to retain the assembly intact without the need of the two upstruck lugs 9 and 15 and the screw 17.

By using file 1 in its curved configuration it is possible to file parts adjacent to other metal parts without nicking and digging into the latter parts. Thus by the operators holding the file bender with the knob 11 in one hand and the handle 4 of the file 1 in the other, the desired filing may be performed without fear of injuring the parts to which the part being filed is attached.

While in order to comply with the statute, the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown,

but that the means and construction herein disclosedv comprises a preferred form of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claim.

What is claimed is:

In combination with a file having a tang on the rearward end thereof, a curved file holder for holding said file in curved condition: comprising a curved frame, a clip on one end of said frame that retains the forward end of said file, an open socket on the other end of said frame, a retaining member for receiving and securing the tang of said file, said retaining member having an extension thereon effective to seat within said open socket of said frame so that said file is held in curved condition over said curved frame when said frame, said file, and said retaining member are assembled, an upstruck lug on the end of said frame adjacent to said retaining member, a corresponding lug on said retaining member, and means for drawing said lugs toward each other to adjusted position and for holding the same in said position.

References Cited in the file of this patent UNITED STATES PATENTS 424,018 Muller Mar. 25, 1890 1,659,765 Canterbury Feb. 21, 1928 2,193,400 Fore Mar. 12, 1940 FOREIGN PATENTS 6,187 Norway Aug. 9, 1897 

